The present invention relates to a method and to an apparatus for monitoring the quality of lubricating oil (hereinafter also designated merely as lubricant) that is in a gear mechanism or a machine and that contains effective materials or substances.
In machinery and equipment construction, and in particular in gear mechanism technology, the quality of the lubricant is an important influencing factor that determines the availability, the reliability and the safety of the overall drive train or the lubricated structural components. Oil-soluble effective substances, such as, for example, various extreme-pressure and anti-wear additives, are added to mineral oils, mineral oil products, or synthetic oils to improve the lubricating effect or the chemical properties. Differences in the quality in the various lubricants represents a competitive criterion. Experience in the maintenance of gear mechanisms has shown that even the best lubricants age and must be exchanged. In this connection, one changes over in stages from the scheduled oil change intervals more to oil change periods that are a function of the condition of the oil or lubricant. The criterion is the classic oil analysis by means of which the physical and chemical parameters of the lubricant are analyzed.
Unfortunately, clearly measurable criteria that can be a measure of when the quality of an oil is insufficient, do not yet exist. For this reason, for example in the wind power industry, it is a standard and required by regulation, that for wind power units the towers must be regularly climbed, oil samples taken, and the oil quality subsequently determined in a laboratory. If individual parameters of the oil become impaired, the lubricant is exchanged already for safety reasons. To be able to determine the suitable point in time for changing the oil, these analyses require a well-equipped analysis laboratory, as well as a precise withdrawal of sample. Determined are the viscosity, the pH, the quantity of foreign particles, and their composition. The properties can be determined only with very expensive analysis equipment, and can be evaluated only by specialists.
Immediate indications of possible danger to the gear mechanism due to an inadequate quality of the aged oil are possible only in the final stage of the lubricant. A large number of oil-changing criteria can be found in the technical literature; these criteria in part contradict one another.
It is therefore an object of the present invention to provide a method and an apparatus that, on site, enables a rapid and reliable monitoring of the quality of the lubricant in a gear mechanism or machine.